JPS6160927B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for fixing piles used in construction and civil engineering.

(Problems to be Solved by the Invention) We are proposing a method for fixing piles that has excellent bearing capacity and frictional force by expanding the tip and middle portions of the pile body in several places using an expanding agent. However, when an expanding agent is put inside the entire hollow pile body, a large amount of expensive expanding agent is required, resulting in a very expensive pile that is not profitable. Furthermore, when the entire pile body was filled with an expansion agent, there was a problem with the strength of the pile.

(Means for Solving Problems) The pile fixing method of the present invention uses a pile end fitting to close the opening at the end of a hollow pile body, which has a plurality of slits formed at several locations around the end and middle. After inserting the pile body into the soil from the pile end fitting to the desired depth, insert a pipe with a smaller diameter than the pile body into the pile body to create a gap between this small diameter pipe and the pile body. A method in which a gap is formed, an expanding agent is filled in the gap, and a small diameter pipe is filled with concrete, and the slits formed at the tip of the pile and in the middle of the pile body are enlarged in multiple locations over time. It is.

(Example) The present invention will be described below based on an example shown in the drawings. Reference numeral 1 denotes a hollow pile body made of metal or synthetic resin material, and the tip 1a and the middle 1 of this pile body 1 are
A plurality of slits 2a, 2b, and 2c are formed around the circumference of b. It is desirable to form two or more slits 2a on the circumference of the pile body 1, respectively. The length and number of slits are determined depending on the expansion performance of the expansion agent, which will be described later. These slits are preferably formed along the axial direction or inclined to the axial direction, but the middle slits 2b, 2c, etc. may be formed substantially at right angles to the axial direction. Reference numeral 3 denotes a pile end metal fitting which is fitted into the opening at the end of the pile body 1 to close it.
It is desirable that the pile tip metal fitting 3 is a bullet-shaped metal fitting with a pointed tip. This is because when driving the pile body 1 into the soil, it is important that the soil does not get into the pile body and that it is easy to drive.

In this way, the pile body 1 and the pile tip fitting 3 are formed,
After fitting the pile tip fitting 3 into the tip opening of the pile body 1,
This pile body 1 is driven into the soil or buried. In the case of burying, the pile body is buried in a hole drilled at a predetermined depth using an excavator or the like, and then the hole is backfilled. Moreover, in the case of burial, the tip of the pile main body 1 may be closed in advance without using a pile tip metal fitting.

After putting the pile body 1 into the soil to a desired depth, a pipe 4 having a smaller diameter than the pile body is inserted into the pile body 1. By inserting the pipe 4, a gap 5 is formed between the pipe and the pile body 1. An expanding agent 6 is put into this gap 5. Expanding agent 6 is an agent that, when mixed with water and filled into a target hole or cylinder, hardens and expands to cause planned cracking and expansion in the target object.For example, a product manufactured by Onoda Cement Co., Ltd. The name is Bleister etc.

After approximately 15 to 24 hours have elapsed after the expansion agent 6 was injected into the gap 5 created between the pile body 1 and the pipe, the slit portions 2a provided at the tip 1a and the middle of the pile body 1... It is expanded by the curing and expansion of the swelling agent. The expansion agent 6 is in the gap 5 from 2 to
Expands 3 times. Since the tip and middle of the pile expand and expand in a knot-like manner at multiple locations, the pull-out resistance increases and the tip supporting force also increases.

Incidentally, an expanding agent 6 is injected into the gap 5 formed between the pile body 1 and the pipe 4, and the pipe 4 is filled with concrete. Therefore, a strong pile body with a concrete column inside can be obtained.

Further, the expanding agent 6 may be filled into the gaps 5 only in the portions forming the slits 2a, and the other portions may be filled with concrete. Furthermore, mix the expanding agent and concrete to create a gap 5.
It is also possible to inject it into the body.

The expansion agent solidifies to some extent and expands inside the pile body over time. Therefore, the amount of the expanding agent flowing out from each slit is small, and the expanding agent forms a lump and expands the diameter of the pile body at each slit.

(Effects of the Invention) The construction method of the present invention as described above has the following effects.

The expansion agent that expands several parts of the pile body only needs to be filled into the gap between the pile body and the pipe.
Only a small amount of the swelling agent is required, and it is possible to obtain piles with excellent frictional support at an economical cost.

Since concrete is injected into the pipe inserted into the pile body, the center of the pile body can be made into a strong concrete column.

[Brief explanation of the drawing]

Figure 1 is a front view of the pile body using the construction method of the present invention;
Figure 2 is a bottom view of the same, Figure 3 is a perspective view of the pile tip fitting,
Figure 4 is a diagram of the pile body with the pile end fitting attached to the tip of the pile body and is about to be driven into the soil. Figure 5 is a diagram of the pile body being driven into the soil to the desired depth and an expanding agent being added to the pile body. Figure 6 is a perspective view of the pipe inserted into the pile body placed in the soil, and Figure 7 is a diagram in which several parts of the pile body are enlarged by the expansion agent. 1...Pile body, 1a...Tip, 1b...Middle,
2a, 2b, 2c...Slit, 3...Pile tip metal fitting,
4...pipe, 5...gap, 6...inflating agent.

Claims (1)

[Claims] 1. The opening at the end of a hollow pile body, which has multiple slits formed at several points around the tip and the middle, is closed with a pile tip fitting, and the pile body is inserted into the soil from the end of the pile tip fitting. After the pile is inserted to a deep depth, a pipe with a smaller diameter than the pile body is inserted into the pile body to form a gap between the small diameter pipe and the pile body, and the gap is filled with an expanding agent and the small diameter pipe is inserted into the pile body. A pile fixing method characterized in that a pipe is filled with concrete, and as time passes, the slit portions formed at the tip of the pile and the middle of the pile body are expanded at multiple locations.